Re: No, it's stupid
Any alarm system with the keypad integrated with the base station and/or siren is pretty much useless.
Or even worse than useless if there's a sticker advertising the specific brand, since then burglars will know who to target since they know the alarm system can be trivially disabled.
And yes - this actually does happen. Including burglars specifically targeting those houses which display particular stickers.
The same thing does apply to wireless systems as well, although to a smaller extent since radio jamming requires more than simply smashing the panel. See for example http://www.thesidebar.org/insecurity/?p=856