We should not restrict anyone from being able to run a node, nor should we make it much harder (somewhat is acceptable) for those that already are running them, just because a group of 'scoundrel' want to pay for their coffee using Bitcoin.
Nothing wrong for paying for coffee with Bitcoin or even the bitcoin network. But to whatever extent there is a choice between monetary sovereignty and direct blockchain small retail sales-- the latter can be replaced using a lot of different mechanisms (for coffee? even centralized ones, for godssakes!); and the former cannot... I don't really think there is a fundamental mutual exclusion, but avoiding it will require being smarter, and not just cramming things in. Bitcoin: It's not a big truck.
Of more concern than "coffee" is transactions which have nothing to do with Bitcoin, transfer no Bitcoin value; and are just stuffing data into the bitcoin network because it's available; and some people have been going around selling the idea of ignoring the Bitcoin currency and saying that the system is just a big public database. This sort of stuff is out of scope for the Bitcoin system and endangers it survival when the cost of carting around a zillion 'stock transfer' zero value txouts overwhelms the public's interest in Bitcoin. ... and they've been a major driver for calls to remove Bitcoin's resource controls. I think totally separate assets need to have their own networks and fates, or otherwise one becomes an externalized cost on the other and can act as dead weight that removes the viability of the combined system.