What do they do?? It says i get $4,000 every time its clicked, so what does that mean??? Other pople click it??

After each match you get a 'free and easy' $12,000 just for selecting 3 sponsors.

Under the Club tab, click economy. You'll then have your income/out goings info. At the bottom left there is a button 'Sponsors' click that and it takes you to your sponsor window. Once there you'll see 3 grey squares at the bottom with a link below each one. Hit that then select a sponsor, do it for all 3 grey squares and you get the 3x $4,000. This can be done after each match