The latter absolutely should get just as hostile a reaction. The only thing it provides you over the former is that it at least guarantees you that the author went to the trouble of creating a deb.

Actually, it should probably get even more hostile a reaction, since installing it that way usually means you won't get any updates for it. If you absolutely must install software from a (trusted) source other than your distribution, adding a source and then using `apt` is the way to go.