I still do it in person because it shows initiative, but if they do request online applications only, ye’d best respect their wishes. It shows that you know to follow directions, which is one think I’m pretty sure most bosses look for. I also take down the phone number and call them in person to keep up, at least this way they’ll know you’re really wanting.
As for making good impressions, I’ll save that if I get an interview. Not speaking for every single place there is, but as long as you’re polite and friendly, I’m not sure that the receptionist’s impression of you is asked for by most employers, unless there’s something extreme to have been noted.
As for it being better online or in person I guess this depends. Beyond following the specifications of a potential employer I don’t know much if it’s best or not, especially on the point of view of someone responsible for hiring.
But it’s a hectic society in which we often strive for convenience. I’m happy with online applications only because it saves so much time while job searching.
It probably saves them time too, since they don’t have to sit there and wait for influxes of paper resumes and then store them somewhere, they can just do it from the computer.
Actually I denno if that’s much better but eh, as I say, beyond following directions I’m not too worried about whether or not the employer finds one or the other better as long as they hire my poor ass haha.