If the only way to get vegetables into your kids at the moment is to hide them, I say go for it. Hide them everywhere you possibly can.
Making sure kids get enough vegetables every day is really critical in ensuring they get the range of vitamins, minerals and phytonutrients they need everyday to support growth, development and good health. The fibre and low energy density in vegetables also helps fill children up and reduces the risk of overeating and becoming overweight.
The flip side to the argument is that in order for a child to learn that vegetables are Ok to eat and that there is no need to run for the hills at the mere sight of broccoli, they need to be given the opportunity to know they are eating it - to have it served to them to taste, feel, smell and see.
I certainly also support this argument and agree that it is important for children (and adults) to learn that these foods can be enjoyable - but achieving this is far easier said then done. For a child (or adult) who is not used to eating and enjoying vegetables a big chunk of green stuff on their plate can be really overwhelming, but there are some tips and tricks to make this transition easier. Check out, It's Not a Coincident that my kids love veggies and my 15 tips to reduce fussy eating before your child turns 2.
Best of both worlds:
Ultimately my advice is to do both; serves some veggies on their plate for them to become familiar with but also smuggle them into their diet wherever you can. The vast majority of my Main Meal recipes use this tactic - there are veggies hidden within but the meal is then serves with a side salad or a side of steamed veg.
Hidden veggies aren't just for kids:
This little tactic to hide veggies in the meals I serve is not just for the benefit of the kids, it helps make our meals go further (my husband eats a lot!), it reduces the energy density of the meals (which means that even though my husbands portions are big, the amount of energy he takes in from that serve is less then it would be otherwise, so its a great tactic for anyone who is trying to lose or maintain their weight). Don't forget that veggies are important for adults too and the vast majority just don't eat enough so by all means 'sneak' them into your own diet too.
To help you on your way to meeting your recommended intake of vegetables check out my post for the Gutsy Challenge, it gives you all the info you need to know about servings of vegetables, a fruit and veg reward chart to help kids track their progress and a weekly meal plan (** please note that the competition attached to this post is now closed)