As someone who has been punched in the face a couple of times..... Intentionally and non and a few of the other things mentioned by Dan . Having trained in other MA's where you learn by getting hit in face and other areas with punches and kicks and never even talking about the lethal stuff until u attain some advanced level. My original statement that " the first time more than half present aikido people were to get hit as a part of regular training, they would be gone" $$$$$ would leave dojo and and business down as a result, stands. Oh and of course let's not forget insurance liability for you legitimate dojo/ business owners.
In fact many people , maybe older , maybe tired of being punching bags come to aikido , " to not get hit any more" . Maybe they get suckered in by the "it's not fighting" line. ( that is still open for debate) Which is very very very hard to live up to, if u push the envelope on your training whatsoever .
Pretty much , Dan nailed it. Going " cold" , In other words , contolling or inhibiting the adrenaline dump is why people , whether they know it or not , train. As you get older the expenditure on your body gets too costly never mind losing or winning....
How real and competitive you want to get and where and how u train is entirely up to you.
Just don't pretend it's something else.