What others are calling, 'normal' in this thread I would call highly unacceptable for any 9mm Glock. As far as I'm concerned it looks like the slide wasn't properly heat treated. I've got Glock pistols around here with anywhere from 15,000 to 25,000 fired rounds through them - Many of these rounds were really hot, too! NONE of my slide bottoms show even 1/10th the slide peening that yours does; and, two of these Glocks are 45 ACP caliber!
Will your G-34 work? Yes, it will. Will your G-34 shoot straight? Yes, straight enough. Is that kind of slide peening typical of, 'many' Glocks? In my experience, fewer pistols rather than more. To my mind this is just more proof positive that Glock pistols ain't what they used to be. I've got two very good early third generation G-21's that are everything that they should be and are standing up well. I've, also, got a G-19 with what has, so far, been a, 'manageable' BTF problem. Unless I come across an early Model 19 with a serial number prefix lower than, 'L' I am positive that I ain't never going to buy another Glock anything.
PS: Unclebob gave you good advice! The only question I have is, 'Do you actually know how to touch-up a lock block?'