When I was playing in a 1950s-style rock'n roll/rockabilly band (many years ago), we used to play at functions or in pubs where the clientele were very much into that style of music - old teddy boys with the drapes and suede shoes, etc. A few of them could get very annoyed if you didn't play some of the material exactly like the record, or the particular recorded version they liked, and - of course - being a trio, we used to adapt the music to suit our line-up. We also used to jam in the middle - mainly to extend the number so that the dancers could have a good jive. 99% of the time we did very well and were very much appreciated - so much so that we were getting bookings nearly every night of the week at some times of the year - so we must have been doing something right.

However... we played one venue where a particular "ted" and his girlfriend just stood in front of the band and criticised every number for not being "like the record". As I was doing all the guitar work and most of the vocals, I was getting increasingly, shall we say, pissed off. Finally, at the end of some more criticism about an Eddie Cochrane number, I went to the front of the stage and addressed him thus:

Me: "I suggest you go and get a shovel."

Ted: "Why?"

Me: "So you can go to Eddie Cochrane's fucking grave, dig the fucker up, and tell him to sing the fucking song himself."

Ted: (strangled squawk)

Me: "And then you can shove the fucking shovel up your arse."

General laughter and applause from the rest of the audience (thank heavens) and no more from said ted...