MaRKuS-DJM

Just to say some bla-bla-bla. In general case you are right, but consider the application that calculates its CRC and, if unpacked, CRC will change and this CRC is involved in come computaions, not just in idiotic

cmp eax, CRC
jnz ok_lets_go_and_kick_their_asses

I met such examples. One was packed with Aspack and after unpacking (really clear one - IAT, TLS, etc) stopped working.