There are three reasons you'll get a lot of keikies:
- The plant is genetically programmed to do so, as is common in some phalaenopsis species.
- Your culture is lacking for the particular plant; this is a strategy to reproduce when things "ain't quite right" for good flowering and potential pollination.
- Both.
Removing keikies doesn't conserve energy, it wastes it.
The plant has already expended some resources growing what it has, so removing them and throwing them away is a waste, right from the start. Plus, a keiki photosynthesizes, incorporates nutrients and produces fuel, storing them and water that is shared with the mother plant it is attached to. Removing them may prevent the further commitment of resources, but it also takes away the plants' ability to produce them at a greater rate.
If you're getting a lot of keikies with nobile dendrobiums, I suggest you leave them be and try to find what the plant needs that you're not providing.