in Llorentes case, he got a salary of 3.5M a year, which is 0.5M more than Vucinic and Giovinco, and 2M less than Tevez, so he was in range of our other strikers, while he was brought to start next to Tevez. when comparing to other stars of the team at the time he signed, Buffon had 6M, Pirlo and Vidal who were still on their 2011 contracts had 3M (both extended during that season for higher salaries iirc). but the situation wasnt the same as it is now, because we were coming off our just 2nd scudetto and the team wasnt as star studded as it is now, the few ones we had were "made" and "revived" by us, we werent as attractive of a destination as we are now etc.
with Emre Can, you had 3 internationally established top mids already here, and now you sign this young one that still has a lot to prove, and give him the highest wages among them off the bat. its no surprise Pjanic already seeks a new, better contract. expect some others to do so as well