I knida know what you mean..
I had the same thought reading it..However-
Back then the old marvel universe books had the individual strengths of wrecking crew members as 10 tonnes each, (the same as spidey) and the Wrecker when not sharing it with them at 40 tonnes.
But I think in a lot of stories since then that's been ignored as their strength levels seem to be all over the place..(especially the Wrecker)
So I'm not sure if they've ever received any kind of official power up, but given some of their appearances since secret wars, it would explain a lot if they had had one.
Still I do agree that as slow as they are, Spidey and Deadpool should still be able to take them down.