Just a small observation. A company will ALWAYS try to make its product sell more. What you are saying is mere speculation, and it can't really be proven. Looking at it from a business perspective, all the crossovers with OP and DB, as well as the magazine covers were to help Toriko increase its sales even more. It just shows that the magazine had a lot of faith in the series. It did become a success in Japan, just not as big as the series we refer to as the "Big 3."
What trying always to make its product sell more has any thing to do with the expectations and something not being indication of certain expectations? People always tell that Toriko was a disappointment because it failed the expectations. The problem is that it didn't! After the anime had a good volume sales boost, the anime had a amazing TV rankings, and it had a lot of merchandising that sold.
From a business perspective a crossover was never used to get a boost in sales, even less a big boost. Crossover were always used as little extras, just like special episodes. Why would it now be used for something more?
You have tons of crossovers being made all over the place. Detective Conan with Lupin III, Hello Kitty and Chopper, Doraemon and Shin-Chan, Attack on Titan and Marvel, ... None of them brought a significant boost, so why would companies start using it like that now. And no, I'm not saying it has no effect, but it doesn't compare with the content of the title, its direct marketing and the word of mouth. At most it has a little spice effect.
So yes Toriko 1st episode crossover with One Piece was made to give a little push in Toriko beginning, just like Gintama 1st episode special was made with that same intention.
With Toriko in the cover comment I probably didn't specified enough, I'm talking of the group covers where Toriko appeared in the front. That has only to do with how the title is doing in the magazine, and it doesn't has nothing to do with its situation in the volumes. As I said, Toriko by the volume 13 was only selling around 210k copies per volume, that is a fact. And that value isn't much(for a super popular series), is basically the same as Nurarihyon, but the series was still appearing in the front all that time.
How is what I'm saying, that it wasn't the company expectation hat it would sell as much as the biggest selling mangas of the magazine, just a speculation? While I can't never be 100% sure, unless I know someone inside of the company, is not hard to see that only someone to stupid or to arrogant would expect a title to get in the top of the industry! More when talking of a title doing what Toriko was doing. Caution is something that you must have in a business, certainly animation companies are also like that.
For example, just for Toriko to get the volumes sales of Bleach at its peak, 800k, it would need an anime boost of 280%. Do you really think that someone in Toei and Shueisha was delusional enough to seriously expect such kind of boost? Not saying that when the time comes and the title seems to be able to achieve that value they will not make everything possible to get it, but if it doesn't do nothing like that there will be nobody disappointed.