I'm going to let you in on a little secret here: showrooming wasn't invented by our generation, so don't feel special. It has always existed, as long as vendor A had more knowledgable sales people and vendor B had better prices. Heck, some mail order companies even took advantage of showrooming in the past by having small showrooms for their products while selling the bulk of their merchandise through mailorder.

Some businesses hated this, even before the Internet, so there is nothing new there either. On the other hand, a lot of businesses learned how to deal with it. Offering after market services and support is a prime example of this. B&M can virtually always do this better than mail order (including online). Building relationships with customers is another way. That is especially true with smaller businesses. (It's hard to do with the big businesses who are complaining about showrooming because their staff tend to be unknowledgable, indifferent, and there is a high turnover rate.)

Now I'm not going to say that I agree with showrooming or that I participate in it. Yet I am not going to claim that it is immoral because there is actually nothing wrong with it. If a business can't convince a customer that they should buy the product in their store because it is cheaper online, then they did a poor job in communicating the benefits of buying from them.