*installation is not "free" at bestbuy.. there is about $150 tacked onto the price of the alarm when you buy it there.. thats your install fee.. they WILL NOT sell you an alarm without install (even if ur gonna do it yourself).. thats why the alarms sold on the internet are WAY cheaper..
to be an authorized DEI retailer, the system come with basic install included (which is different from free install) and since they don't warranty anything that was not sold &installed by a authorized dealer,they dont want it to be sold by itself, and you are incorrect we do sell R/S's and alarms with out install all the time, you just dont get the package price (since you are not buying all the items that make up the package)
alarms are sold online cheaper because they are being sold by a non authorized dealer and then they have no warranty.
its a package deal and when it is being sold they take the install price off of the system and charge it to labor (which then saves you money since its not being taxed) so that they can have installers to do the job, no labor, no installers.