The good thing about consent in this case is they can just "return" the gift by paying you their portion of the bill, and if they don't consent isn't really violated. You went from owing the restaurant to owing them.

But why take the joys of life and make them difficult? Let your friend enjoy himself by being generous.

While this behavior is joyous and enjoyablefor you, not everyone may share your point of view. Some find joy in paying their own way. Let others choose for themselves instead of deciding for them.

Paying a bill isn't forcing anything on anyone. It literally doesn't involve them, it's between the payer (the gift giver) and the payee (the restaurant).

If you pay someone else’s debt without their consent it absolutely involves them. Of course the restaurant doesn’t care who pays.

How could it possibly? They aren't a party to the transaction.

They are. Picking up someone's tab is analogous to extending them credit. There are people out there who hate being indebted to anyone.

No, credit happens only by mutual consent. Paying someone's bill does not obligate them to reimburse you; extending them credit does.

It's still analogous to credit. Many people will feel like they owe you if you do it.

So is it disrespectful to want to gift someone a meal? I don’t understand why it has to be so black and white.

Also the consent thing really sounds weird. Do you honestly go around making value judgements about when people did or did not seek your consent to this level of granularity? Why?

Again I think if the first place you go to when offered a free, meaningful and well intended gift is consent, you internally have an issue that you need to handle.