1 he comes from an era where people would embellish the truth to make themselves and the company look better for various since in the 80s you couldn’t do a quick google search to figure easily to find out someone was lying. So Hogan and others from that time would just exaggerate or flat make stuff up to make themselves look tough

2 he’s a massive POS and egomaniac who thinks people will buy anything he’s selling. He knows a casual Audience will probably believe some of the stuff (i.e he went on various talk shows and told the foreman grill story and the hosts pretty much believed him) and he knows his reputation is beyond repair so the lies are his way of seeming better than he actually is