I admit I accidentally got an area covered in snow from making 2 golems. In my defense though, I built about 90% of the thing that got covered. and in the pre-release the AI of them stopped em from going over 2block high edges. now they do. I still spammed tons of them. But as many ppl I talk to can vouch for, i have them in a contained box. That I nuked last night cause i have better plans for them.
On a separate note, to build a golem you need to place blocks. to place blocks you need lands rights. A) should reconsider who you let live in/near your town if they gunna spam golems. B) maybe zerg could set it so snow blocks cant be placed in nature (like water or lava sources).
Banning them completely or making a spawn limit however.... I vote no. Cause for some people the golems can be used in Games like for Snakejay's Themepark for target practice. Or for NPC storekeepers in town pubs,stores,etc. Or simplely used as Sentrys to protect town from mobs (instead of lacing ground with torches or slabs), Sure they dont kill the mobs but can still distract them from killing players off guard.
EDIT: What happen to modstick? VERY useful in killing the golems left around without damaging players stuff.