Because of the argument that people are willing to pay more for their ticket. Regardless of what price the tickets face value is, if there is someone out there willing to pay £50+ for a ticket than that is potential revenue/profit for the artist/management.
How would you like it if you were selling a guitar and advertised it in the paper for £50. The buyer comes to see it and says "cool i'll take it, i could get £75 for that easily". Dont you think you'd want to change your mind and re-advertise it the next day for £75? The point is, if there's someone out there willing to pay £75 for your guitar, you should be the one to get that.
I'm sorry, but whatever way you put it, buying tickets with the intent to sell them on straight away is just a horrible practice.
If the seller didn't have the initiative to sell it at the right price, then of course they don't deserve the cash. You telling me if someone was selling an xbox360 for £50 and you knew you could sell it for £150 - you'd tell the person who was selling it and not snap up a chance to make a quick buck?
You telling me these people on TV that buy things at carboot sales / antique shops and sell them for more at auction are as bad?

