wordplay - I need to clear my table... again!

^{Note: This puzzle is fairly easy. While I can't stop more seasoned or high-rep users from answering, I would appreciate it if it were left to newer members of the Puzzling community. Thank you!
Note 2: Despite appearances, there are not any tags missing from this puzzle.}

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I thought I was already done clearing tables at the end of the day, but then I found this set of pictures on a table I was certain I had already cleaned

Now, cleaning the table again isn't a huge inconvenience for me, but the paper does raise some questions. Three questions, in fact, and I want an answer and an explanation for all of them!

1. What sort of puzzle is on the paper?


2. What is the message that that puzzle is trying to convey?


3. What did noticing the paper force me to do?

Answer

The answer is

rebus

Because

The first thing is ("recycle" minus ("bicycle" intersect "nitrogen/water cycle")) = "re"

The second is (("blockbuster" minus "block") xor ("lobster" xor ("lobe" minus "e"))) = ("buster" xor "ster") = "bu"

The last thing represents rot13(F), which is of course "S".

And to answer the questions:

1.

 A rebus, of course! 

2.

 the word "rebus". 

3.

 It forced you to do a rebus of the table you had previously cleaned.