Your right probably not the best thing to be worrying about right now, but when our sun begins to deterriorate in about 10 billion years, then they can start to worry about were that can take us. Is it more important to find this stuff now, and let the future take us there or be scrambling for something we can live on in the way future?
And no we wouldn't have to be constantly moving, just have to stay on the top of the planet, which is probably only about a quarter of the planet, and use the rest for maybe resourses.
Correction: After just over 1 billion years, the extra solar energy input will cause Earth's oceans to evaporate and the hydrogen from the water to be lost permanently to space, with total loss of water by 3 billion years.[18] Earth's atmosphere and lithosphere will become like that of Venus. Over another billion years, most of the atmosphere will get lost in space as well;[15] ultimately leaving Earth as a desiccated, dead planet with a surface of molten rock.
Courtesy of:
http://en.wikipedia.org/wiki/Red_giantAnd for you wikipediaphobes, references: 1.^ a b c d e Zeilik, Michael A.; Gregory, Stephan A. (1998). Introductory Astronomy & Astrophysics (4th ed.). Saunders College Publishing. pp. 321–322. ISBN 0030062284.
2.^ Color of star ranging blue through orange
3.^ Measurements of the frequency of starspots on red giant stars
4.^ orange sphere of the sun
5.^ The Cambridge Atlas of Astronomy (2nd ed.). Cambridge University Press. 1988. pp. 255. ISBN 0-521-36360-8.
6.^ Harvard University search for orange-yellow clumps
7.^ a b Sackmann, I.-Juliana; Boothroyd, Arnold I.; Kraemer, Kathleen E. (1993). "Our Sun. III. Present and Future" (PDF). Astrophysical Journal 418: 457. doi:10.1086/173407.
http://articles.adsabs.harvard.edu/cgi-bin/nph-iarticle_query?1993ApJ...418..457S&data_type=PDF_HIGH&whole_paper=YES&type=PRINTER&filetype=.pdf. Retrieved 2008-07-23.
8.^ Pogge, Richard W. (2006-01-21). "Lecture 16: The Evolution of Low-Mass Stars". Astronomy 162: Introduction to Stars, Galaxies, & the Universe.
http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit2/lowmass.html. Retrieved 2006-12-29.
9.^ "Main-Sequence Stars". Stars. The Astrophysics Spectator. 2005-02-16.
http://www.astrophysicsspectator.com/topics/stars/MainSequence.html. Retrieved 2006-12-29.
10.^ Richmond, Michael. "Late stages of evolution for low-mass stars".
http://spiff.rit.edu/classes/phys230/lectures/planneb/planneb.html. Retrieved 2006-12-29.
11.^ "Red Giants". HyperPhysics (hosted by the Department of Physics and Astronomy of Georgia State University).
http://hyperphysics.phy-astr.gsu.edu/hbase/astro/redgia.html. Retrieved 2006-12-29.
12.^ Strobel, Nick (2004-06-02). "Stages 5-7". Lives and Deaths of Stars.
http://www.astronomynotes.com/evolutn/s5.htm. Retrieved 2006-12-29.
13.^ "The fading: red giants and white dwarfs". Free.
http://nrumiano.free.fr/Estars/fading.html. Retrieved 2006-12-29.
14.^ Jones, Hilary (22 December 2006). "Clues to the death of our Solar System". COSMOS magazine (Sydney).
http://www.cosmosmagazine.com/news/952/clues-death-our-solar-system.
15.^ a b Pogge, Richard W. (1997-06-13). "The Once and Future Sun". New Vistas in Astronomy.
http://www-astronomy.mps.ohio-state.edu/~pogge/Lectures/vistas97.html. Retrieved 2007-01-23.
16.^ Hecht, Jeff (02 April 1994). "Fiery future for planet Earth". New Scientist (Boston) (1919).
http://www.newscientist.com/article/mg14219191.900-science-fiery-future-for-planet-earth.html. Retrieved 2 July 2010.
17.^ Palmer, Jason (22 February 2008). "Hope dims that Earth will survive Sun's death". New Scientist.
http://www.newscientist.com/article/dn13369?feedId=online-news_rss20.
18.^ Sun is a powerhouse - Death in our solar system
-Penguin