[mPReDiToR]

One of the best reasons to pay after you eat is so you can question the bill in case of an unsatisfactory dish or service.

Tipping is optional in many areas, and can depend on the quality of the Front of House staff. Picking up a payment for £100 and finding £110 that was left because you've done a good job can be motivation to some people.

[JohnFen]

I don't think he's arguing to pay the bill up front, just to ask for the bill up front to avoid the whole "waiting for the check" thing. The idea doesn't appeal to me because I'm not confident that I know what I'll be ordering in total that early. Dessert, for instance... I rarely order dessert, but sometimes at the end of a meal, I do. I can't predict at the start whether or not that will be the case.

But I do have a different habit to speed things along: instead of asking for the check, waiting for it to arrive, then giving my card, I just hand the server my card in the first place and say I'm paying the bill. That eliminates one whole back-and-forth cycle.