I agree that many people over embellish the size and weight of a fish, though I do not believe there is any malicious intent to do so. Quite simply I believe that many people are so excited to catch a big bass coupled with little to no experience with landing decent size fish, that they figure it must weigh more than just a few pounds. Then you have those that just like to tell fish stories. Many of us fall into both these categories at some point in their fishing career. Or even week.
I had the very opposite of this initial thread happen to me, and wonder if it has happened to anyone else. I always carry several scales. Mechanical and digital, so I can get a true weight/length measurement for my own log. It was spawn and I was fishing 20 yards off shore with a wacky rigged GY senko, and had been slaying the fish in the early morning. A guy on shore was fishing with his wife. I landed a few fish in front of them, and then ended up landing a nice fish a little over 5 lbs. I was fishing solo, and went Ike during the fight/netting of this fish. I took some pictures and weighed the fish. As I was revving the fish, he guy from shore asked me how big it was, and so I told him, just over 5lbs. He apparently believed I was telling him yet another fish story, and quite candidly told me no way, it was a 3lber tops. I was approx 50 yards from this guy at this point. Part of me wanted to tell the guy to feel free to swim over to my boat and he could see by himself, instead I said that's what my three scales said pal, I don't know what to tell you. Really left a bad taste in my mouth...until I hooked up with another fish and forgot about his comments.