Tanzer claimed that there has been an influx of visitors to historic European sites. And, because of this, they will eventually struggle to cope with the numbers.
"You can see the strain not just on the tourist experience but on the actual fabric of the city and on the residents there," Tanzer explained at a conference in London recently, The Times reported.
"Overcrowding in key destinations is becoming a pressing issue. Without controls, we know tourism can kill tourism."
This unchecked influx of visitors could damage local economies, he warned.
He added: "People will stop going. Or the danger is that you will get the footfall but you will not get the value of tourism - people spending in restaurants or shopping and supporting the local economy. If they can't get around the city you are going to lose value from tourism even if the numbers are going up."
"Customers have certain expectations and rights regarding travel accommodation and other services, irrespective of how those arrangements are purchased, whether is it a question of quality, safety, or protection of the customers' money." An ABTA spokesperson said today.
"We believe that new distribution models such as peer to peer accommodation, particularly those that are run on a professional, commercial basis, should be held to the same standards as traditional models; both industry and holidaymakers should be assured that any commercial enterprise is properly monitored and regulated.
"One issue that is becoming increasingly pressing is that of overcrowding in some major tourist destinations. The growth of the peer to peer economy, and the arrival of tourists from new source markets, are responses to a growing demand for tourism.
"But at some point soon we shall need mechanisms to manage numbers in crowded destinations, for the benefit of the industry, the customers and the destination residents. Logically, these measures would need to take account of both hotel visitors, and peer to peer accommodation users," the spokesperson added.
While hotels and hostels have seen their visitor numbers dropping, San Francisco start-up Airbnb has seen a relentless rise in its popularity.
It now operates in 34,000 cities in 191 countries - drawing in 900,000 visitors to Barcelona alone last year - allowing private owners to rent out rooms directly to holidaymakers.
It's even received the support of the Rio Olympic Games, winning a contract for a reported 20,000 rooms and the backing of George Osborne's "sharing economy" plan.
However, the travel company is not unanimously popular.
Julian Ledger, chief executive of YHA Australia, told a parliamentary inquiry that some Airbnb properties are being operated like illegal hostels, The Guardian reported.
There are now laws in San Francisco that restrict Airbnb hosts from renting out rooms for more than 90 days a year and Iceland is looking to make the home-sharers register as businesses.
The company insists that whereas hotels will centralise guests in city centres, Airbnb spreads tourists across communities, lessening the impact of travel and introducing tourism as an economy to new communities.
It told MailOnline Travel: "It is disappointing - but not surprising - to see attacks on new forms of travel that put money in the pockets of local residents and support small businesses outside hotel districts.
"Experts agree that Airbnb helps more people to travel and spreads guests and benefits beyond city centres to more families, communities and local businesses - many that haven't previously benefited from tourism.
"Home sharing is an economic lifeline for countless families and we are proud to work with cities around the world to support them."
Tanzer's comments have received a great deal of criticism on social media, with comments suggesting that as a representation of hotel and hostel agents he is just hitting out because he is feeling the pinch.
Regardless, there has been an increase in reports of holiday destinations restricting tourists on the grounds of overwhelming numbers.
In January, Unesco's World Heritage sites officials said that in Machu Pichu, Peru, the sheer number of visitors was weakening the stonework of the Incan monument. Mont-Saint Michel, France, seconded this as it revealed tourists mill about "shoulder to shoulder, four to five thick".
After Omori in Japan was added to the International Council on Monuments and Sites list it went from a sleepy town to welcoming almost one million tourists. The community was unprepared and is now looking for ways of limiting the impact.
Similarly when Lijiang Old Town in the southwestern province of Yunnan, China, was awarded World Cultural Heritage status in 1997 it saw traveller numbers swell to over 16 million and outside hoteliers move in.
Koh Tachai in Thailand has gone so far as to bar visitors as a permanent solution for preventing further irreversible environmental damage from tourism.
Following 2.5 million people descending on the Cinque Terre U.N. World Heritage park in Italy last year the town is now ticketing visitors to ensure they keep below a 1.5 million barrier.
In a similar move the Santorini in Greece is restricting the number of boats that dock on its shores. Following the 790,000 visitors to the island in 2015, officials are keen to preserve and protect the picturesque port so from this summer it will only allow 8,000 passengers to disembark a day.