Please recycle if possible and use any USB charger you have.
Of course if you have a 0.5amp and wanted 2.0amp to charge quicker etc. If the device says 2.0amp better to stick with this as the upper limit.
The device in general should be handling the charging, the wall USB charger is really just a transformer that can be plugged into any USB device (in the old days it was a little bit different, meant 2 chargers or dedicated USB cable was needed for different device but I think that does not apply anymore).
lithium batteries are actually very dangerous in general and more so when being charged and when discharging for a long time at its lower limits. I dare say the plug-in wall charger would never be tasked with handling the charging characteristic's of a lithium battery as you can connect any device/USB cable due to the USB standard.