Pet Transplants

How can anyone in the world justify pet transplants when around the world people are starving to death. You pet is not that important. Let it die like all pets do.
If you have to do it then I think you should give the same amount it costs to have the transplant to one of the proper charities around the world to help people in the less well off world.
And finally some questions that I do not have answers to:

• Where to the organs that are used for these transplants come from ?

• Does someone breed cats and dogs, etc just to provide the organs ?

• Are there animal organ harvesters who kidnap other people's pets to provide the organs ?
  
• Humans reject organs because of incompatibilities and all have to take suppresant drugs so do pets have to take similar drugs ?

• Which drug company worked on these drugs if they exist ?