camper88's quotation is very incomplete, missing out some important facts, the full "explanation" goes like this and of course both theories are BS:
There are 2 theories as to the identity of "Mr. Jimmy," who appears in the third verse. It could be a reference to Jimmy Miller, who was The Stones' producer at the time, but it might also refer to Jimmy Hutmaker, a local character that wanders the business district in Excelsior, Minnesota, a trendy artist community outside Minneapolis near Lake Minnetonka. Hutmaker, who is known as "Mr. Jimmy," has some disabilities but seems mentally sharp most days, although he tends to talk to himself a lot. He walks miles every day and is cared for by the local shop owners, whom he still visits on a regular basis (he turned 72 in 2004).
The Stones performed in Excelsior on their first US tour in 2004, and were not well received. Mick Jagger went into a local drugstore to get a Cherry Coke. Back then a cherry coke was a coke with real cherries in it and drug store soda fountains were the place you usually found them. The store didn't have cherry cokes and Mr. Jimmy, standing in line behind Jagger, commented, "Well, you can't always get what you want." Mr. Jimmy was at the Stones next show in Minneapolis. Legend has it that Jagger sent a limo to pick him up, but it is more likely that a local businessman worked it out so he could go. (thanks, Chris Hall - Athens, GA, and the good people at the Excelsior chamber of commerce)
The source is [
64.233.183.104]
... unfortuantely Songfacts is everything but reliable.