It's a personal choice. There's never an "excuse", but I got no problem with roids. As long as you don't abuse the pain-killers and alcohol, and use the steroids properly, I personally think it's fine. They are wrestlers. If management wants a wrestler to add 20-30+ pounds to their upper body, how are they gonna do it? Of course there is pressure. But it's always a personal decision. As long as the user isn't a heavy drinker or into any other drugs, steroids are an easy alternative to what most wrestlers/bodybuilders believed they have earned the right to use. Hours spent in the weight-room can be meaningless if things like genetics and metabolism get in the way. Benoit and Guererro were pretty short guys. Around 5'10 or 11". You think they would be World Champions without their physique thanks to roids? Not a chance.
So in conclusion, steroids are an easy alternative for wrestlers to get their physique, but it's all based on personal choice, regardless of pressure. Just like some kids choose to smoke pot because of peer pressure and some choose not to, etc. Everybody's different. But most wrestlers who use roids are heavy weight-lifters. You don't get jacked using roids if you never pick up a dumbell. Most of these guys, like I said, believe they have earned the right to use steroids. Physical setbacks or lack of time due to travel could be some of the reasons these guys turn to roids. However, the main reason is because most wrestlers are obsessed with getting big, therefore they will do so by all means necessary. Bodybuilding is an obsession.