I don't see these questions as problematic. I will preface this by saying: If you wish to downvote, that is your prerogative; the act of voting is anonymous and completely subjective. However, I would discourage downvoting, closing, and other such actions for the following reasons.
Many people do not even know Google reverse-image search exists. Unfortunately I don't have any specific polls or stats on this, but I have had many people ask me the origin of a specific image, after which I point them to the reverse search, much to their astonishment. We are an anime and manga site, not a tech site, so we should not assume people to be familiar with anything beyond Google's basic image and text searches.
Additionally, the question itself will contain a lot of searchable, textual details. Let's take the piyo-piyo apron question for example: It contains a title referring to the term "piyo", as well as the apron, and then shows an image. If we then imagine someone, without the image, who searches "anime girl piyo-piyo apron" on Google, they could easily end up on our site. That's a win-win: We get traffic, and our users get an answer.
In essence, I am opposed to viewing reverse-image-searchable questions as "poor" because there is little awareness of Google's reverse-image capabilities, and because having such questions improves our chances of drawing in someone with the same question.