The airline pilot may well have paid out £50k+ to get his licence - at the same time as taking at least a year off from doing any paid work. Only if he is really, really lucky will this have been paid by an employer. If any training is paid for by an employer, it's often clawed back, or the pilot is bonded to the company for some time - effectively captive and working for the lowest wage paid to any pilot in the company.
Having paid out that amount of cash, he (or she) will have absolutely no guarantee of a job, and if he fails a medical at any time could be out of the job for good.
Typically, a newly qualified pilot will hawk his CV round all the smaller carriers, "hire a plane and pilot" outfits, flying schools, etc to get "a" job. If he's really lucky, this first job will pay his living bills - a lot of them who end up in flying schools as instructors make money that a lot of plumbers and electricians wouldn't get out of bed for.
If anyone has watched "Bush Pilots" or similar programs, the guys camping while trying to get a job are in this position - trying to get their first job and a step onto the bottom rung of the ladder. And you'll also have seen that a lot of them have to go home empty handed. People may look at airline pilots (especially captains) and think that's a cushy job for a lot of money - but it can take a decade or more to work your way up there, and a lot never make it.
So yes, I think it's fair to say there's "some difference" between a bus driver and an airline pilot !