The Three Caballeros are characters which Disney seems to cherish somewhat. Although they don't do regular meeting and greeting, they do occasionally appear at the Mexico pavilion at Epcot and often feature in various parades and shows around the Disney parks.
Limited Time Magic is the way Disney describe Meets and Greets with all three Caballeros. I love the costumes for Panchito and Jose and it's fun to see Donald in his sombrero. The area used for these meetings is beside the Mexico pavilion and although Jose and Panchito rarely appear, Donald is regularly available for photos and smiles in this area.
The Three Caballeros also make rare appearances at Disneyland California Adventure, particularly around Christmas and the celebration of Viva Navidad. As well as meeting and greeting they also appear in the Viva Navidad parade.
The three amigos have also been known to appear at Tokyo DisneySea (although not seemingly at the Saludos Amigos Greeting Dock).
Mickey's Soundsational Parade at Disneyland is where you will find Donald's Fiesta Fantastico float, featuring Donald, Jose, Panchito and, gloriously, the Aracuan bird. Donald stands atop a colourful drum with hanging pinatas whilst Jose and Panchito lead in front, along with colourfully-dressed dancers (some dressed as pinatas!).
Disneyland Paris has featured the Three Caballeros in a special Disney Dreamers show (I believe this is a promotional VIP event). One sequence of this is actually the Aurora Miranda song and dance scene from the film staged live with an actress playing Miranda, various male dancers and Donald, This sequence is followed by a scene with Donald, Jose and Panchito singing The Three Caballeros.
I have also found a different version of the show on Youtube called Disney Dreamers Everywhere which not only features the Three Caballeros but also Burrito, the flying donkey and his little Gauchito friend!
Another show to feature Jose Carioca and Panchito Pistoles, although not Donald oddly, is the Happy Hallowe'en Amigos show at Tokyo Disneyland.
At Tokyo Disneyland they also feature in a hallowe'en parade.
I find it fascinating that for such an obscure and often forgotten film of the Disney Canon, the characters of Jose and Panchito have such a colourful presence, even if only rarely, at so many of the Disney theme parks. When you consider the fact that Bambi and its characters (aside from Thumper) rarely appear even for special events, it is such an odd thing.