whether or not you add flavourings, artificial or natural, is just a personal preference dm. It's neither right nor wrong. The advantage of using them is that you'll be able to more precisely control the flavour of your wine to what you want. Thats part of what its all about. If you want to drink your homebrew, but don't like it, then it kinda defeats the purpose eh! You gotta brew how it suits you at the end of the day. It could be worth considering using something like jam or juice instead of strawberries tho, it'll probably be cheaper and less hassle. if you use jam then you'll probably need some pectic enzyme, unless you buy some expensive jam which would kinda defeat the cost cutting purpose. And you don't get the fun of playing with fresh fruit.
Its good that arturo highlighted the flavour issue tho because it can be a source of disappointment if the results are way off what you expected. On the other hand when you make a country wine that tastes like a decent grape wine .....