You're possibly expecting your garden to generate the uniform produce that you see in the grocery store - in reality, there is a lot in the garden that doesn't match that state of perfection. The nice surprise is that though you get some funny little fruits or veggies, you get to enjoy the monster pieces! I've had grapefruit-sized tomatoes this year that would never make their way to the grocery store (they wouldn't fit in the partitioned boxes!) I don't know any serious gardeners who throw away any but the worst looking produce. You have a knife, cut the spot off.
Same with the lettuce, tear of the brown spot and eat the rest. The discards go into the compost.
Holes in leaves are going to be there, too many may slow the plants' growth or production of a crop, but you can't avoid all of them. Organics is about having a healthy garden, but a hermetic environment with no pests isn't the goal - that's the Ortho or Amdro view of the world. Keeping the pests to a minimum and under control and allowing the beneficial bugs to do their job an a garden with healthy soil (under a good mulch) is the goal.