What razor said, along with just about every present or former team official, draft guru, draft guru wannabe, etc. when discussing this time of year. And yes, all teams do their due diligence on pretty much every player, however, not all evaluations are created equal. Teams do not bring everyone in for a formal workout or take each player out to dinner, or have a two hour meeting with all draft eligible players. In fact, contact with most players is limited to a quick discussion at the combine or pro-day, along with the film work and scouting reports.
Who is everybody? Former coaches? Former GMs?
Every team has a draft strategy, they go out to the combine and Pro Days, records times, drills, etc... It's called evaluating talent and again, teams don't just look at one player from the college, they look at multiple players at various positions, again, it's called evaluating. Once they determine where all the players rank on their draft board, it is a deck of cards from there... I'll admit, there is a little smokscreening during the actual draft process because the draft is unpredictable and teams just don't know who will make a gamble and jump in front but again, a team has to be completely stupid to look at just one player because they are trying to signal smoke.
So while it is expected and no big deal to have cursory contact with a player, the extra attention given to certain players will highlight exactly what the team's plans are unless they do something to throw other teams off. Usually this is done by working out or having extended contact with players the team is not necessarily targeting or going the opposite direction and not showing any special interest in a player they really covet (like the Panthers did with Beason). All teams want to muddy the water in order to throw everyone off the trail of what they're really doing.