Because First Choice do not have a customer base built up from Doncaster, they are at the moment selling seats below market value to build up at these bases, you may find similar bargins flying from Newcastle.
The reason they include meals is a technicality between tour operators (computers have difficulty talking to each other) rather than First Choice being generous. Still a perk to the flying public though.

I am looking for cheap flights to malaga for next week for 5 days but the prices are very expensive, please could anyone point me in the right direction.
Many thanks

easyJet have a sale on at the moment for travel before 8th June.

Flights are from £19.99 one way including taxes.

You might have to be a bit flexible with your times and maybe play around with dates a bit to get a good deal but at this late stage they may be as cheap as you get.

Thanks
Mark

PS: Other options which you may have already tried include:-

Ryanair
Monarch
Jet2
Thomsonfly
Flyglobespan

amongst others.

Without knowing the date and airport you want to go from, its difficult to know which airline would be best for you.

Thanks
Mark