See also: Aliyah to the Promised Land
In all of these three verses, the hebrew root commonly translated "scout" or "spy" is Y-T-R. A more appropriate translation is "tourist" or "ambassador". Three reasons for this:
first, twelve conspicuous men cannot be hidden, and twelve notable chieftains constitute an foreign embassy. There is no attempt at a covert operation.
Secondly, a spy looks for the weak points to exploit, and these men were looking only at the good things that they could respect or enjoy. These tourists returned conspicuously with souvenirs, and spies don't do that.
Lastly, in the following generation Joshua sent two men who actually were spies, and we need a distinct term for them. The hebrew root given there is M-R-G-L, which is more accurately reflected by the word "spy"
The sin of the tourists (the yaturim) was to exaggerate the positive qualities of the land. This led them to speak evil of themselves. (Lashon haRa).
For this central insight, and for the distinction with the second generation spies, I must credit a source sheet from Yeshiva Darche Noam, that was taught to me at Pico Shul in LA. The further analysis and translation of "yaturim" as "tourist" is my own.