It should never be an excuse for poor service. However, I'd be amazed if anybody here thought that "clicking" or getting on, or whatever you want to call it, didn't result in a better punt. That applies to plumbers and postmen too (just to use daffs example), who if you get on, are more likely to say "Ok, I'll have a quick look at that extra thing I didn't quote you for" or "no worries, I'll leave it with a neighbour" instead of throwing it behind a hedge.
Surely?... Unless you're determined not to engage with anybody beyond your transaction, in which case.. Fair enough I guess.