I never was one to enjoy going to super markets or big DIY places but this is my theory about shopping trolleys.
At the place of manufacture they insert a micro chip this enables the trolley to steer itself to any part of the supermarket you don't want to go ,Also the ones that have a hidden brake to slow you down to keep you in the supermarket longer.
Another pet hate is those who use them as prams and allow thier sprogs to stand up thierfore depositing all kinds of nasty things in the trolley and there is an amplifier chip which will amplify tantrum noises.
I did suggest to Tesco that they should at least sterilize each trolly after use but i think my suggestion fell on deaf ears.
Long live internet shopping.[
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