Actually, no.
While hairspray can be an effective deterrant, it is NOT just as effective as pepper or mace. At best, hairspray in the eyes will be an irritant and may cause temporary blindness but it will NOT incapacitate or markedly reduce the aggressor's ability to harm (especially in a small enclosed room - like a hotel room). Also, hairspray is meant to be dispersive and has a very broad spray pattern and thus is ineffective outside of a couple of feet AT BEST. Pepper spray (and also foam) is meant to be used in a stream and has an effective range of several yards.
Pepper (active ingredient Oleoresin Capsicum -- OC) spray is an irritant, causing severe pain when in contact with skin. It also acts as an inflammatory agent, causing inflammation in the mucous membranes of the eyes, nose, throat, and lungs. Temporary blindness occurs on contact with eyes along with intense burning, causing them to swell shut. Loss of balance and muscle coordination may occur along with severe skin irritation, difficulty breathing, and gagging. Psychological effects may include anxiety and panic, especially when breathing difficulties are experienced. (from Wikipedia)
My first exposure to OC was in a large warehouse setting where we were undergoing training in its use. One unlucky volunteer was sprayed and while it didn't take him down immediately as a TASER would, his eyes swelled shut after a few moments, he had trouble breathing, his eyes were streaming tears and he was bent over. HOWEVER, he was able to continue his attack for several steps and it did not act instantaneously. Therefore, the suggested methodology in small spaces is to spray and get the fuck out of his way and stay beyond his reach. Tripping works well in a pinch
Meanwhile, in a space with 30' ceilings and about 2000 sq. ft., within a couple of minutes, that one spray had dispersed enough where we ALL started coughing and our eyes started watering. And I believe the sprays we were using were only 2,000,000 scoville units (
http://www.chemsoc.org/exemplarchem/entries/mbellringer/scoville.htm) and not law enforcement grade.
In short: hairspray is NOT the same or just as effective as pepper spray. Keeping in mind that pepper spray is used as bear deterrant, ask yourself: "Would you spray a bear in the face with hairspray?"
If you answered yes, please stay out of wilderness areas and for the love of god, leave the poor bears at the zoo in peace!