Hi BlueSea Corporation,
I am not associated with Laminar Research.
You do what you like with Steam. Waste your money if you want too. As you have the official version you will receive updates far quicker than through the steam version You won't get any support from Laminar Research. Steam is a third party product taking a commercial advantage of all of the work carried out by Laminar in developing X-Plane 11.
Steam created a disc version before Laminar Research released their official disc version. At that time the only available version from Laminar Research was the digital download. Laminar Research has no connection with Steam.
If you have a steam problem you may be lucky to get support from other flight simmers.
As mentioned don't waste your money.