It's not nearly so simple.
DXCC, for instance, does not have the 50-mile rule. For DXCC, all contacts must be made from the same DX entity. Remote operation is allowed as long as transmitter and receiver are located in the same DXCC entity. (DXCC Rule 9)
WAS has a 50-mile rule (Rule 3), but it is common to earn WAS by starting from scratch if you move or have a station outside your original 50-mile circle. There is nothing in the WAS rules to prevent you from earning WAS while using a remote station within 50 miles of your home or other station, or making a separate application for WAS completed entirely by remote sites within 50 miles of each other.
ARRL has studied the issue extensively and has specifically not prohibited remote operating in its contests. There are rules about "remote receive sites", but these refer to sites that are remote from the operating station, not the operator's location. As long as the rule that "All transmitters and receivers must be located within a 500-meter diameter circle, excluding antennas." is followed, there is no reason you can't operate an ARRL contest from a remote station.
I am inclined to disagree with the folks who oppose use of remote stations. While the idea of "paying for QSOs" is a nice sound bite for opponents, please consider:
* Not every ham has the ability to put up their own station. (eg, apartment dwellers, college students, HOA victims)
* Club stations are often made available to members for personal use, and their use (under a personal call) has not drawn such objections, even though the club station may be much better equipped than the ham's home station.
* Remote operating includes not just the heavy-weight stations that are subject to hourly rental, but also club shacks that are more modest and made available to members over the Internet.
* Remote operating also includes operating ones own station via the Internet, perhaps while out of town. (I, for one, have been known to operate my own station remotely this way.)
* Finally, "paying for QSOs" by renting time at a huge contest site is very little different from buying the best gear, the best antennas, property at the best location, etc. Those with funds to spend have that advantage over others regardless of the way those funds are spent (locally vs remotely). Having a huge, expensive contest station at your home doesn't mean you are particularly skilled, and likewise, paying for use of a remote station doesn't mean you lack the skill. It's simply a question of how you allocate your resources.
For what it's worth, I don't operate stations other than my own remotely, but I do sometimes use my own call at my club's station (which is permitted by the club). Having been in circumstances where I couldn't set up my own station (and I still don't have the station I really want), I am very sympathetic to those who want to rent the facility from others.