You cannot harm wireless USB adapter by pulling it out immediately. The only downside of yanking out USB device is that if this device has a filesystem (e.g. flash stick, hard disk), it may be in an inconsistent state, thus possible data corruption). This does not apply to wireless network adapter.
However, the connectors do wear out. According to wikipedia:
USB connections eventually wear out as the connection loosens through repeated plugging and unplugging. The lifetime of a USB-A male connector is approximately 1,500 connect/disconnect cycles.
So, if you connect/disconnect your device say 4 times a day, each and every day, it should last about a year. Bear in mind, however, that the female socket in your computer or USB hub wears out too. The actual wear rates depend on the quality of your hardware, how careful you are, etc. They are hard to estimate.
The 1500 insertion cycles are minimum values needed to get USB certification, some manufacturers exceed them. Quality matters.