I think a lot depends on just where our heart is, and it's often very hard to tell where someone else's heart is.
It has been said that you can tell a lot about someone's priorities by looking at their checkbook. There's certainly some truth in that but it doesn't tell you anything about their prayer life and how they spend their time. Sometimes writing a check is the soft option when it comes to caring - it's easy to write a check and figure someone else can get their hands dirty doing the real work, but much harder to actually roll up your sleeves and get busy actually doing the work that needs to be done. Whether it's helping in a soup kitchen, volunteering at a social club for the old folks, adopting a troubled child, actually doing the work can often cost a whole lot more than simply writing a check and figuring Someone Else will get involved. Of course larger charities are more likely to make a big song and dance about their major donors, whereas the person who gets busy volunteering doesn't necessarily get any public recognition at all.
If you're about the public adulation the chances are your heart is in the wrong place.
As far as people who "look much like the world" I suppose it would depend on exactly how they look like the world. I've seen people use all sorts of silly circular reasoning to try and prohibit the things they dislike, with "reasoning" (the term used in its loosest possible context) that goes along the lines of "the world drinks alcohol, we should not be like the world, therefore we should not drink alcohol". Such bizarre arguments are often presented as if they were unshakeable, but then the people who present them dislike being told "the world wears clothes, we are not to be like the world, therefore we should not wear clothes" or similar. In many ways we should expect a Christian to look much like the world, in that Christians may ride the train to work, work in regular employment, collect a paycheck, hang out with friends in the evening, maybe visit the bar and have a couple of drinks, watch a sporting match, and so on. You know, all the things that "the world" does. To a casual observer they may look just like their secular counterparts. To a casual observer it may be difficult to differentiate a Christian from a non-Christian, and in many ways I don't think that has to be a problem - how exactly are we to be visibly different from a non-Christian, as observed by someone with no more contact with us than happening to be riding in the same train carriage as us? On the other hand, if it becomes clear to people based on knowing us for a time that we don't actually care for widows and orphans, don't love God, don't love our neighbor, and want nothing more than our own life of hedonism, they may be reasonable in asking whether we are truly Christians.
