While your question was poked fun at by some, this exact question came up for a friend and I yesterday. Why? Because weight is touted as a "pro" for some amps and we didn't know why. Your question elicited some good reasons.
Amplifiers weight
What does amplifiers weight has to do with performance?
im trying to decide between this 3 amps
parasound JC5 73 pounds, Anthem STR 60 pounds Michi S5 by Rotel 132 pounds
I can get them around the same price
my speakers is modified klipsch KLF 30
preamp is Michi P5 and a pair of SVS SB16 ultra Sony Hap Z1 and Cambridge Azur 851N
i really like the looks of STR amp
im trying to decide between this 3 amps
parasound JC5 73 pounds, Anthem STR 60 pounds Michi S5 by Rotel 132 pounds
I can get them around the same price
my speakers is modified klipsch KLF 30
preamp is Michi P5 and a pair of SVS SB16 ultra Sony Hap Z1 and Cambridge Azur 851N
i really like the looks of STR amp