The pensioner was most recently caught by a supermarket security guard after stealing items from two stores in Stafford on December 12 last year.
When quizzed by officers she told them: "I'm bored I suppose. I just wanted to get out of Crewe."
Humphreys was flanked by security guards and hunched over a shopping trolley as she made her way into Cannock Magistrates Court to admit two counts of theft on Friday.
The OAP was fined £80 and told to also pay £135 costs and a £30 surcharge.
Sentencing, chairwoman of the bench Mrs Lisa Elkington-Bourne said: 'You have got quite a prolific history from over the last few years so it's difficult to know how to deal with it.
"We are going to fine you."
The court heard Humphreys had 38 previous convictions, all for matters of dishonesty, committed after she reached her mid-seventies.
When asked why she had taken goods worth £23.50 on December 12, she told police officers: "I don't know why I did it, I just took them, alright?
"I don't know. I don't get anything out of it."
The prolific crook was caught by a Sainsbury's security guard after she took stationery worth £4 from the supermarket.
In her shopping trolley there were two packs of Pampers nappies and baby milk worth £19.50.
The items had been stolen from the Wilko store in the town earlier that day.
The court also heard police had issued a warrant for Humphreys' arrest after she failed to arrive at court for a scheduled hearing on December 30.
Neil O'Driscoll, defending, said she had tried to get a bus to Cannock from Crewe but was unaware where she had to go and got lost.
He added: "But she managed find her way to the court today."
Previously, JPs were told how Humphreys would target stores and has stolen items such as clothes, alcohol and a breast pump.
Her probation officer Darren Vernon told the court at a past hearing: "She has travelled around Staffordshire and Cheshire on public transport and committed offences.
"She knows what she is doing is wrong, she says she is bored and needs to fill her time.
"The main reason for her doing this is boredom. She lives alone.
"She has seven children but the only one she has contact with lives above her.
"She has acquired the record of a heroin addict in his late teens."