ExploderWizard
Hero
Yea, I was talking about actual sieges, not metaphorical ones.
Metaphorical? You do realize that being trapped somewhere for a period of time is an actual siege and not just a metaphor right? The physical trappings do not define what a siege is.
Lots of spells screw up world-building, even when they aren't at-will. Continual flame, fabricate, wall of iron, etc. What's one more thing to tacitly ignore so we can get on with playing?
It is the nature of magic to make the normally impossible become possible. Thats why it is magic after all. The difference is that with those examples, no matter if you used magic or not to achieve those effects there is a cost involved. A spell slot is a resource cost. Completely at-will magic is absent any such consideration.
I'm not against the concept of cantrip magic that has minor effect, that is less powerful, and takes less power, than a first level spell. In my own B/X house rules, magic users power points for such effects equal to 10 + character level so their capacity to power them rises with level. This allows the performance of enough minor magical effects to last a decent adventuring day without making them infinitly spammable. A thing without cost is used without consideration. If the use of something has a cost, however minor, then using it still requires a decision.
IMHO no magic ever should be completely free of cost or consideration.